A cleaning apparatus may comprise a rotatable brush that, when brought into contact with a surface to be cleaned and rotated, will perform a scrubbing action. To enhance the working of the apparatus, the surface may be wetted.
FR 2,797,895, for example, discloses a rotatable brush assembly for use in a street cleaning device. The brush assembly has a hollow support shaft, formed by a hollow cylinder. One end of the cylinder is closed, whereas another end may be connected to a water feed. The cylindrical wall of the shaft is provided with multiple rows of bristles, and has multiple openings arranged there between through which water, which may be fed into the hollow cylinder via the water feed, may flow outwards. The centrifugal force associated with the rotation of the shaft projects the water onto a surface to be cleaned. There, the water softens the dirt, which may subsequently be removed by the moving bristles.